Watching for the mouse or whatever that surfaced and dived back down.
Something like that, although I don't actually write it down. I remember every swim and the distance from the original high water casting spot.
I did message a mate this week after I got home: "After last night's phone dilemma, it crashed, I lost a carp this morning, hook pulled. Monster crab pop-up sliver on a coated braid Multi-rig. I'd played it from aiming at sneaky squirrel around 40metres. It ran right, so I waded out with my net, got it to go left, and it went past middle rod and hook just popped out. Not a good session. So upset I packed up a day early".